4.1.1 The static chambers can be used to compare the susceptibility of different materials to the colonization and amplification of various microorganisms under defined conditions.

4.1.2 Chambers operated at high relative humidities may be used to perform worst case scenario screening tests on materials by providing an atmosphere where environmental conditions may be favorable for microbial growth.

4.1.3 Use of multiple chambers with different environmental parameters, such as a range of relative humidities, permits the evaluation of multiple microenvironments and allows investigation of materials under differing environmental conditions.

4.1.4 Drying requirements for wetted materials may also be investigated. This information may be relevant for determining material resistance to microbial growth after becoming wet. These conditions may simulate those where materials are subjected to water incursion through leaks as well as during remediation of a building after a fire.

4.1.5 Growth rates of microorganisms on the material may also be investigated. Once it has been established that organisms are able to grow on a particular material under defined conditions, investigations into the rate of organism growth may be performed. These evaluations provide base line information and can be used to evaluate methods to limit or contain amplification of microorganisms.

4.2 These techniques should be performed by personnel with training in microbiology. The individual must be competent in the use of sterile technique, which is critical to exclude external contamination of materials.

1. Scope

1.1 Many different types of microorganisms (for example, bacteria, fungi, viruses, algae) can occupy indoor spaces. Materials that support microbial growth are potential indoor sources of biocontaminants (for example, spores and toxins) that can become airborne indoor biopollutants. This guide describes a simple, relatively cost effective approach to evaluating the ability of a variety of materials to support microbial growth using a small chamber method.

1.2 This guide is intended to assist groups in the development of specific test methods for a definite material or groups of materials.

1.3 Static chambers have certain limitations. Usually, only small samples of indoor materials can be evaluated. Care must be taken that these samples are representative of the materials being tested so that a true evaluation of the material is performed.

1.4 Static chambers provide controlled laboratory microenvironment conditions. These chambers are not intended to duplicate room conditions, and care must be taken when interpreting the results. Static chambers are not a substitute for dynamic chambers or field studies.

1.5 A variety of microorganisms, specifically bacteria and fungi, can be evaluated using these chambers. This guide is not intended to provide human health effect data. However, organisms of clinical interest, such as those described as potentially allergenic, may be studied using this approach.

1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.7This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.